Tophat -- we all feel for you. This is one of the most hotly discussed subjects on Stovebolt (and every other antique vehicle related board I've ever been to, it seems

). Everyone will give you opinions and advice based on personal experience, but it seems there is no consistency among any of the states, and even within the states themselves. It seems like here in Maryland, the process is different every time I do it (same office, different day). So good luck. Most states are okay with antique pickups and little trucks. But when you bring them an antique medium duty/commercial vehicle, they get flummoxed like they can not comprehend that anyone would want to own and drive (let alone *restore* ... gasp!) an old commercial vehicle. So, not being able to think outside the lines, they stick to what they know -- it was built to be a commercial vehicle so a commercial vehicle it must remain. Besides, they get way more money from you that way. Best thing any of us can tell you is what it appears you've already done -- research the process as best you can for your particular state, county and municipality, fill out the forms and then give it your best shot. And be prepared, as you have discovered, to have to give it multiple tries. I've had the best luck on Wednesdays in the middle of the month. Best to get guidance in writing to show the LE professional when he/she pulls you over (because whatever MVA said, they didn't tell the cops ...). Bottom line: You have not done anything wrong. We all go through this. Welcome to the club.
Does AZ have a collector/Historic tag you can use? Some states don't care about the weight for a collector tag. If they *do* make you go by the weight, don't under guess it. DOT tickets for being over weight are expensive.